1964 Volume 10 Issue 3 Pages 257-265
The purification of Rhizopus delemar lipase was undertaken to compare its enzymatic properties with those of the crystalline Aspergillus niger lipase (1). From culture filtrate of Rhizopus delemar grown by shaking culture, the enzyme was purified by ammonium sulfate fractionation, Duolite A2 resin treatment, SE-Sephadex column chromatography, acetone fractionation and gel-filtration by Sephadex G-75.
The specific activity of purified enzyme thus obtained was 2, 600-fold higher than that of the starting culture filtrate. Olive oil hydrolyzing activity of the enzyme was maximum at pH 5.6 and at 35°. The enzyme was stable at the range of pH 4 to 7 and at temperatures lower than 45°, but quickly inactivated above 50°. A weak esterase activity found in the enzyme preparation would be considered to be shown by the activity of the lipase itself.
Remarkable differences of the enzymatic properties of Rhizopus and Aspergillus lipases are found in their isoelectric points, turnover numbers and reaction conditions.